If the line _BC_ represents the productive power of a unit of labor in a region which is sparsely peopled, and the line _B'C'_ represents the productive power of a unit of labor in a densely peopled region, we may assume that _AC_ and _A'C'_, which are equal to each other, represent the product of a unit in either locality when, general progress being precluded, the difference in the density of population should have been leveled out. Move people at once and in a wholesale manner till there is nothing to be gained by further moving them,--let pressure of population on the land be fully equalized,--and you may be supposed to create a condition of uniform productive power for laborers of a given grade in the entire region. The horizontal line _AA'_, which is everywhere the same distance above the line _CC'_, represents the universal level of the productivity of labor in such a theoretical condition. The line _BB'_ represents the actual and different levels of the natural earnings of labor in the different regions. Assuming that all other static adjustments are made, but that the equalization of population has not taken place, labor will earn the amount _BC_ in one place and the amount _B'C'_ in another. Somewhere it will earn an amount represented by the vertical line descending from _D_ and somewhere that expressed by the line descending from _F_, while there will be places where the earnings of labor are measured by the line descending from _E_, which is the amount that labor would everywhere create and get if the population could be quickly made normal in all regions. The standard of wages for the whole of the great region, largely European and American, which constitutes the economic center of the world, shows varying levels in different countries and parts of countries, and the actual rates in every place fluctuate about this proximately normal standard for that place, the standard rate in one locality being higher than that of another. The line _A'B'_ exceeds in length the line _AB_, and this expresses the fact that equalizing the pressure of population on the land in different regions adds more to the productivity of labor in the region now crowded than it deducts from that of labor in regions now sparsely peopled. The overcrowding does greater and greater harm the further it is carried, and therefore taking away a surplus of people from a region which has suffered greatly from overcrowding affords a relief which more than offsets what is lost in other places by a moderate increase of population. Moreover, the fact has to be recognized that at present there are ten square miles of sparse population for one that is very densely peopled, and reducing all to an equality would add only slightly to the number of inhabitants of the regions that now contain few of them.[1]